<!DOCTYPE html>
<html>
<head>
	<meta charset="UTF-8">
	<title>checkboxTest</title>
</head>
	<style>
		article{
			width: 250px;
			margin: 0 auto;
		}
	</style>
<body>
	<article>
		<input type="checkbox" value="旅游" ><span> 旅游</span><br>
		<input type="checkbox" value="音乐"><span> 音乐</span><br>
		<input type="checkbox" value="运动"><span> 运动</span><br>
		<span>选中项的信息为：</span><span id="info"></span><br>
		<button id="allBtn">全选</button> <button id="cancelBtn">取消全选</button> <button id="showBtn">显示</button>
	</article>	
</body>
<script src="js/my-js.js"></script>
<script>
	var objArr = $("","input")

	selectAll($("#","allBtn"),objArr);
	unSelectAll($("#","cancelBtn"),objArr);
	showInfo($("#","showBtn"),objArr,$("#","info"));
</script>
</html> 